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Kontract Geotextile

Geotex Exterior Basement Waterproofing System

Cavity drain membrane, drainage and accessories for exterior isolation and direction of groundwater at basement walls, for installation prior to backfill.

For use in conjunction with separate damp proof membrane.
Reduces water pressure and ground movement stress on DPM. Groundwater is filtered by geotextile, enters 8 mm cavity (spaced by integral compression studs) and is directed to drainage at base of wall. Integral backing facilitates movement to prevent damage to DPM (specified separately).
Can be used up to 10 m below ground.

Suitable for use with:

Permanent Insulation Formwork walls.
Wykamol Tecnoseal DPM. (DPM specified separately).
Passive water disposal eg sloping ground.
Active water disposal systems eg sump and pump.
Wykamol sumps and pumps. (Sumps and pumps specified separately).

More about Geotex Exterior Basement Waterproofing System

Product reference:

Geotex Kontract Basement Waterproofing System

Hanging (walls):

[Horizontal].- Provide 450 mm vertical lap joints.
[Vertical].- Provide 150 mm horizontal lap joints


[Aquadrain 60 mm]. - Perforated ground drain.

[Aquadrain 100 mm]. - Perforated ground drain.


[CM Plaster Plug]. - 8 x 70 mm ground for fixings.

[CM Tape]. - For sealing lap joints between Geotex sheets.

[Finishing strip]. - Rigid profiled edging fixed to wall above ground.

Guidance for Geotex Exterior Basement Waterproofing System from Wykamol Group



Outer layer: LDPE. Low density polyethylene geotextile. Water transmission rate: 100 L/m²/sec.

Middle layer: HDPE. High density polyethylene with moulded compression studs. Compression (maximum): 250 kN/m².
Inner layer: PP. Polypropylene slip membrane.
Fix to CM Plaster Plugs set in wall at 150 mm centres, adjacent to top of primary waterproofing. Finishing strip protects top edge.
Overlap membrane joints and tape using CM Tape. Taped joints are not waterproof.
Backfill carefully with earth or other sharps-free fill to avoid irregular stress or mechanical damage to membrane. Membrane is held in place by backfill


Aqua Drain:

60 mm diameter drainage pipe for perimeter drainage of basements. Designed for drainage of water contained behind Wykamol Cavity Drain Membranes and subsequent diversion to sump.
Fully perforated for water ingress. Fitted with continuous geotextile sheath to prevent ingress of particles.
Locate Aquadrain below internal floor level. Encapsulate in granular fill.
Ensure cavity drain membrane extends to level of Aquadrain or below.